Many installations of critical electronic devices are powered by two or more separate sources of electric power. Traditionally, an electromechanical relay has been used as a simple “either-or” mechanism that prevents both power sources to be selected simultaneously. A typical electromechanical relay operates slowly and can take up to 50 milliseconds to change power sources.
Recent developments in electronic devices, particularly computer servers, now require much faster switching times than relays can provide. To meet the increased speed requirement solid-state (transistor-based) relays are used. These switches have 12 millisecond switching times.
Such switches may include triodes for alternating current (TRIAC). TRIACs are controlled by applying a voltage to a “gate” connection. However, TRIACs lack any inherent self-locking mechanisms to preventing multiple TRIACs regulating multiple power sources which are routed to a single load from being simultaneously enabled.
If multiple TRIACs coupled to dissimilar power sources are enabled simultaneously for a given load, the circuit may be immediately disconnected by the circuit breakers. Wiring and/or equipment damage may result from this inadvertent switching.
As such, it may be desirable to provide a method and system for high-reliability switching for power transfer.